 Wait, I can get cash back just for buying the gas I need anyway? Yes, I use it all the time, and I've made around $200. Now pull over so you can download the Upside app before we miss the concert. Download the free Upside app now to earn cash back every time you buy gas. Use promo code WOW25 to get an extra 25 cents per gallon on your first tank. You can cash out anytime right to your bank, PayPal, or as a gift card for Amazon and other brands. Just download the free Upside app and use promo code WOW25.